1. Field of the Invention
This invention generally relates to radio-controlled model airplanes of the type having a wing detachably mounted on a fuselage and, more particularly, to an automatic interlock connector arrangement having a connector stationarily mounted on the wing, and a mating connector stationarily mounted on the fuselage, the two connectors automatically electromechanically engaging each other when the wing is mounted on the fuselage.
2. Description of the Prior Art
In the art of flying a radio-controlled model airplane, it was well known for a person, hereinafter the "flyer", to operate a hand-held radio transmitter and transmit radio signals through the air to an on-board receiver which, in turn, generated control signals for controlling such airplane parts as, by way of example, the rudder, the elevator, the ailerons, the flaps, the throttle, the landing gear, etc. In order to enable the flyer readily to service, repair and clean the components mounted in the fuselage and covered by the wing, it also was known to detach the wing from the fuselage after an outing at a flying site, and to reattach the wing before the next outing at the flying site. The detaching of the wing, which in most designs had a large wingspan, also rendered the airplane more compact since the detached wing could be placed side by side with the fuselage, thereby enabling the airplane to be more conveniently transported to and from the flying site, and stored. Examples of model airplanes having detachable wings can be found, for instance, in U.S. Pat. Nos. 3,935,664; 4,233,773; 3,827,181; Re. 17,564 and 3,633,306.
Since it was customary for the flyer to attach the wing to the fuselage at the flying site before each outing, it also was necessary for the flyer to interconnect one or more electrical plugs supported by the wing, e.g. an aileron plug, which was connected by electrical wires to an aileron servo supported by the wing, to an aileron socket, which was connected by electrical wires to the receiver mounted in the fuselage cabin. The aileron servo was operatively connected to a pair of ailerons on the wing and, in response to an appropriate control signal from the receiver, the aileron servo moved the ailerons. The electrical wires between the aileron plug and the aileron servo, on the one hand, and the electrical wires between the aileron socket and the receiver, on the other hand, deliberately were made long enough so as to give the flyer sufficient length to manipulate the aileron plug with multiple freedoms of movement and to insert the aileron plug into the aileron socket during the attaching of the wing on the fuselage, as well as to remove the aileron plug from the aileron socket during the detaching of the wing from the fuselage.
Although generally satisfactory for its intended purpose, the conventional method of connecting an electrical component in the wing to the receiver in the fuselage of the radio-controlled model airplane possessed certain drawbacks. The interconnected aileron plug and aileron socket, both of which were situated at the ends of relatively long electrical wires within the cabin and thus were free to move around therein, tended undesirably and unpredictably to bounce around within the fuselage cabin during flight and, in some cases, tended to become entangled with various parts within the cabin and especially with linkages and/or pushrods which passed through the cabin to the rudder, elevator, nose gear, engine throttle, etc. The longer the aforementioned electrical wires, the more pronounced was such undesirable, unpredictable movement.
Often the flyer, due to inexperience, inadvertence or ignorance, failed to insert the aileron plug into its associated aileron socket. Also, it sometimes happened that the flyer inserted the aileron plug not into its associated aileron socket, but, instead, into another socket provided within the cabin. This other socket could have been a recharger socket, since the latter typically was not connected to anything at the flying field and thus was available within the cabin to be incorrectly mated with the aileron plug. Less likely was the possibility that the flyer could have incorrectly inserted the aileron plug into a battery socket provided within the cabin. The battery socket typically was connected to the on-board main battery at the flying site to minimize power drain. Even less likely, although theoretically possible, was the chance that the flyer could have inserted the aileron plug into a throttle socket, an elevator socket or a rudder socket, all of which were contained in the cabin within reach of the aileron plug, but each of which was supposed to be connected to respective throttle, elevator and rudder plugs provided within the cabin prior to coming to the flying field. Of course, the failure to insert the aileron plug into its aileron socket, or the insertion of the aileron plug into the wrong socket, rendered the aileron servo, if not other parts of the airplane, inoperative. Sometimes this was not discovered until the airplane was in flight, which was extremely dangerous since some of these airplanes went out of control and have been known to have killed or maimed many people, including innocent spectators. Aside from the safety hazard, this also was a frustrating experience since the airplane would have to be, if possible, landed, the wing detached, the proper connections made, and the wing reattached before the airplane again was ready for flight.
In a manner analogous to that just described for the aileron plug and socket interconnection, certain model airplanes required a plug for a retractable landing gear on the wing to be inserted into a mating landing gear socket on the fuselage. Similarly, a landing flaps plug on the wing of certain model airplanes was required to be inserted into a mating landing flaps socket on the fuselage. Still other airplane designs mounted the engine in the wing, or, in a multi-engine design, one engine was mounted in the wing and another engine was mounted in the fuselage and, in either event, a plug for the engine in the wing was required to be inserted into a mating socket on the fuselage. The more plug and socket interconnections between the wing and the fuselage, the more likely that an omission or mistake could have been made.